S. K. Kotovskaya

Synthesis of new fluorine-containing derivatives of quinoxaline 1,4-dioxides and condensed systems derived from them

The Beirut reaction of 5,6-difluorobenzofuroxan with 1,3-diketones, β-ketoesters, and amides produces 6,7-difluoroquinoxaline 1,4-dioxides. The condensation of 2-ethoxycarbonyl-6,7-difluoro-3-methylquinoxaline 1,4-dioxide is studied. Fluorinated furo[3,4-b]- and pyrrolo[3,4-b]quinoxaline 4,9-dioxides are synthesized and further functionalized by nucleophilic substitution of fluorine and reduction of the N-O bond.

Syntheses of bisheterocycles from 2-hydrazino-3-aminopyridine

Abstract2-Hydrazino-3-aminopyridine reacts with carbon disulfide in an alkaline medium to give 1H-3-aminoimidazo[4,5-b]pyridine-2-thione and in a neutral medium to give 8-amino-3-thio-sym-triazolino[4,3-a]pyridine. The reaction of 2-α-methylhydrazino-3-aminopyridine with carbon disulfide leads to anhydro-1-methyl-3-mercapto-8-amino-sym-triazolo[4,3-a]pyridinium betaine.

Synthesis of 2-hydrazinobenzimidazoles and their antiinfluenza activity

New antiviral agents are being sought in various classes of compounds, including derivatives of benzimidazole. The present study offers data on the antiinfluenza activity and synthesis of the 2-hydrazine derivatives of benzlmidazole which have various substituents both on the nitrogen atom N(1) (hydrogen, methyl, ethyl, benzyl, oxyethyl, and chlorine-compounds I-XV)) and 1,5,6-trlmethyl-2-hydrazinobenzimidazole (XVI).

Synthesis and biological activity of benzimidazole-5-carboxamides

We have previously reported [4] that in 2-hydrazinobenzimidazoles, the greatest antiviral activity is shown by compounds bearing a carboxy or ethoxycarbonyl group in the 5-position. Continuing work on the synthesis and examination of the antiviral activity of benzimidazoles, we have synthesized some benzimidazole-5-carboxamides substituted in the 2-position with chloro-, hydrazine-, and isopropylidene (and isobutylidene)hydrazino-groups (III-XIX).

SYNTHESIS AND PROPERTIES OF PYRIDINE SULFAMIDES AND S-TRIAZOLO(4,3-A)PYRIDINES

Durch Uberfuhrung von 2-Nitro-3-aminopyridin (I) in 2-Chlorpyridin-3-sulfonsaure- Chlorid (II) durch Diazotieren von (I), durch Ersatz der Diazoniumgruppe durch die Sulfochlorid-Gruppe sowie Austausch der Nitrogruppe gegen ein Chloratom (Kotovskaya, S.K.